The industry trend has been to continuously increase the number of electronic components within computing system environments. Compactness allows for selective fabrication of smaller and lighter devices that are more attractive to the consumer. Compactness also allows circuits to operate at higher frequencies and at higher speeds due to the shorter electrical connection distances in these devices. Despite these advantages, providing many electronic components in a small footprint can create device performance challenges. One challenge has to do with thermal management of the overall environment. Heat dissipation, if unresolved, can result in electronic and mechanical failures that will affect overall system performance, irrespective of the size of the environment.
In many computing environments, microprocessors of the computing environment continue to increase in performance, with the active circuitry of the microprocessor chip being driven to an ever smaller footprint and higher power dissipation. Higher power dissipation in a smaller footprint leads to high heat loads and high heat fluxes. Notwithstanding this, reliability constraints often dictate that operating temperature of the devices not exceed a known maximum value.
The existing art has struggled with designing high-performance cooling solutions that can efficiently remove this heat. Current cooling solutions depend on conduction cooling through one or more thermal interfaces to an air-cooled heat sink, possibly employing a spreader or vapor chamber. To further increase the heat removal capability of air-cooled systems, greater airflow is needed. Unfortunately, providing greater airflow is not always possible. Many factors must be taken into consideration in providing ever greater airflow, among which are acoustic noise considerations, as well as power concerns.
As an alternative, liquid cooling methods have recently been incorporated into certain designs. Liquid cooling, however, is also limited by several factors. Liquid cooled microprocessors in the existing art are either immersion cooled in a dielectric fluid (for cooling by pool boiling), or incorporate a cold plate design. Immersion cooled modules have the limitation that the critical heat flux of the dielectric coolant employed is relatively low, thereby limiting the acceptable chip heat flux. Cold plate cooled modules have the limitation that intermediate materials and interfaces restrict the heat transfer capabilities of the module. Consequently, a need still remains for enhanced high performance cooling solutions for cooling high heat flux electronic components.